A currently available optical fiber comprises a core and a clad of circular configuration in cross section. Typically, the core and clad of the optical fiber are made from polymethyl methacrylate and fluoresin.
In such optical fiber for optical transmission applications, it is essential that no optical loss of the transmitted light exists at the end surface by random reflections.
In this regard, smooth-finishing technology of an end surface of such optical fiber is disclosed in Japanese Patent publication No. 15241/85.
The technology is to press the end of an optical fiber against a heating plate having a flat and smooth surface to soften such end thereafter being cooled and hardened to finish it into a smooth surface.
A problem of such prior art technology is, however, the difficulty of holding the end of the optical fiber vertically or at a right angle on the surface of the heating plate so as to control the amount of softening of the optical fiber in its axial direction, thereby making it difficult to obtain an optical fiber of stabilized end quality and to increase productivity of workability. The reason is that it is difficult for an operator to support the front end of the optical fiber in an annular section of a support member standing up-right for urging the end of the optical fiber on the heating plate.
It is an object of this invention to provide a holder capable of controlling the end of the optical fiber in an up-right position or at a right angle with respect to its axis and to control the amount of softening of the optical fiber.